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Topic: Dallas Semiconductor 1-Wire Questions (Read 4854 times)

I'm presently kicking the tires on LinuxMCE, and I have some questions regarding 1-wire support. There isn't much in the Wiki on 1-wire support, so I'm hoping to be able to flesh it out with what I find out...

How is the 1-wire support implemented? Is it direct into LinuxMCE as a DCE device, or via something like the 1-wire file system (OWFS) or digitemp?

What devices other than thermometer chips does it support? Does it support the 1-wire switches for a switched 1-wire network? Does it support A/D and GPIO type devices?

Is the 9097U serial adapter supported in addition to the 9490R USB 1-wire adapter?

Are you able to input a calibration offset amount into the configuration that gets applied to the individual sensors? Due to where most of my sensors are located (phone jack height), I offset those sensors by a degree C so they jive with what my Thermostat reads.

I remember some past forum discussion about data logging not presently existing or about to be implemented... so I guessing that in the 8.10 beta there isn't any way of graphing or otherwise recording temperatures... is that correct? I'm presently feeding a bunch of 1-wire sensors throughout my house into the 1-Wire Weather (OWW) daemon, which feeds that info into Misterhouse, which generates RRD graphs that I can use to analyse tweaks made to the HVAC system.

The driver for the 9490R disappeared in the database sometime ago, most likely due to database corruption at one point. It was implemented as a GSD device, and would need to be re-implemented again, either as a GSD in Ruby, or as a C++ device.

I too am just kicking LMCE's tires and I stumble across this - AFTER spending too much time getting a dinosaur PC i have running the core - a very slow process indeed. Anyway, while searching to see what exactly I need to configure to get one of my 9490 's working, I find this...

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The driver for the 9490R disappeared in the database sometime ago,

PLEASE tell me the driver is on it's way back into LMCE.

1-wire is key for me. My plans include 1-wire for weather and environmental along with slow discrete I/O, and initially X-10 stuff I have (insteon probably later). To that end, I bought a number of 1-wire devices some time ago including a couple of usb dongles.

I am hoping for basic functionality for home automation and media services from LMCE. Initially, my needs are very basic. I hope to grow the system over the next few years AFTER I have a reliable & capable core. For me, a capable core means a growing, very inexpensive - including maintenance & upgrades - collection of software and hardware. I don't have any coding skills ATM. I was hoping to develop some while getting some of the more advanced functions I want working. I need a reliable, predictable platform to do this on though...

I have designed my house to work on totally autonomous systems that do not rely on central control to work. They are then to be integrated (using Linuxmce) to provide additional functionality. Nevertheless, I do not want linuxmce to be a required element for anything to work.

For my 1-wire weather station and sensors I intend to use an NSLU2 (slug) with OWFS or OWW, or somesuch. For my weather station there is a lot of software support already as well as all the information needed to write your own.

By running it on a slug, I can shutdown linuxmce when I choose but all my other non-dependent systems, including weather monitoring, keep going. Here is some information for adding a 1-wire adaptor to the slug.

You might want to think about doing it like that.

(For the record I'm also running a small asterisk server on a slug to route between VoIP and my landline - and vica versa, using an SPA-3102).

To all - so many questions... I have no coding skills and not much useful experience with Linux. please bear that in mind all...

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soooo....write a new driver....we have a considerable architecture for it....either C++ or Ruby...take your pick.

Please do not take this as me being nasty or a - insert colorful metaphor -. I am simply trying to assess the state of LMCE and whether I am appropriate for it - if you get my meaning. Is there no archival data available aid in recovering the loss of the driver? This kind of 'disappearance' suggests this project exists on the brink of calamity. What am I missing? This also suggests interest in 1 wire is almost non-existent in the LMCE community. To me, that means I would be more on my own than I would like to be. As I see it 1-wire is a very powerful and flexible technology that would draw interest to LMCE and so would not be easily 'dropped' - perhaps it wasn't easy... Sorry if this is an excessively simplistic question/observation.

Again, I am asking because I am totally unable to assess this on my own - what is meant by driver in the MCE context? I ask because there is this thing called FUSE (user file system I guess) now in the kernel (?) and this thing called OWFS (One Wire File System) and optionally OWHTTPD etc. I had OWFS/OWHTTPD working alongside MisterHouse on ubuntu 6.? as I recall and owfs had built in support for most, if not all of the available 1-wire chips at the time. I had some problems with Misterhouse that derailed me at that time. Also, MH seemed to be stagnant then and It doesn't seem to have improved since. None of it was all that difficult to get going - it couldn't be, if I did it! Anyway, OWFS provided both flat and tree file structure (I think) that reflected the one wire devices connected to the host beginning at the configured mount point. It gave at least some control over most aspects of the management of the 1-wire net but didn't need to be hand cranked to get useful info to and from devices. I don't know how LMCE handled 1-wire before, or if it still does - just not the usb dongle. Again, ignorance speaking here, but it seems like it would be not so difficult to add OWFS to LMCE. What would then be needed is code to scan the directory tree(s) - multiple 1-wire interfaces to discover what devices are connected, and code to allow proper interaction with the various device types available (driver?). One thing that might require a little bit of extra smart code might be reading the branches of a 1-wire tree. I don't recall just how that worked. There was the possibility of using a 1-wire part to isolate branches to limit the effects of capacitance and thus permit larger nets and more reliable comms. without needing more host interfaces etc.

So:Does LMCE support 1-wire at all now? I still see Dallas Semi and the USB host adapter in child device setup...What host interfaces are supported?Does LMCE use OWFS? (Where is it mounted?)If it doesn't use OWFS, was OWFS considered and rejected? Why?

Any illumination would be appreciated.

Assuming I can get the rest of what I need working in the short term on my dinosaur, I would be willing to do some testing of beta code to help get 1-wire USB going again... I have 2 of the USB host interfaces, and can deploy nearly a dozen temperature sensors within 6 weeks or so. Once that part works I would add some discrete I/O points - perhaps 8 for starters.

To Trentend:

If your remarks were to me, I have a WRT610N that I would use more or less as you describe (dd-wrt etc. etc.) but there, I get no basic functions working without writing my own code. Basic stuff to me is things like turn on the outside lights (some controlled by 1-wire outputs) if the driveway sensors sense incoming traffic and it is dark and play a sound if the time is right. Turn off the outside lights if it is sunrise and there was an override on. Otherwise, turn them off 20 minutes (randomize) after the last outside door in the area is closed or driveway sensors indicate departure. Another example - when you hear x10 code A1on send B all lights on and turn on output at 1-wire address (address) etc.

Gotta go.

I do hope LMCE will work for me and that I will be able to contribute something here eventually.

yay, I love it when people get emotionhal and reactionary...instead of researching facts...

do you see what happened there? we're both on mutually defensive positions... and it's your fault...

perhaps we should start off on better footing?

we do not know what happened with the 1 wire driver...as near as we can tell...the device template was written...but there was no corresponding code checked into our database. oh noes! project on the brink!! oh please....stop it.

so somebody needs to write a driver...given our architecture, this is not difficult for someone with a lesser load on their shoulders than those of us who are actively pushing out the next beta.

I do hope LinuxMCE is for you..but YOU must make that determination...seeing as you took the time to write out reams of text, you could have used that energy toREAD our forums and wiki to find the information you need! everyone's time here is valuable...do not waste it'